The impact on non-Gaussianities of the ISW-Lensing correlation in non-standard cosmologies

Abstract

The detection of non-Gaussianities (NG) in the Cosmic Microwave Background (CMB) is essential to better understand the early epochs of our Universe. One way to observe NG is to constrain the bispectrum, which usually is the largest non-trivial correlation function for most of the inflationary models. However, natural NG arise from late-time evolution and they need to be subtracted from the signal. In this work, we investigate the impact of different dark energy models to the bias induced by the cross-correlation between the Integrated Sachs–Wolfe effect and the weak lensing. More specifically, we compute the predictions for models of dynamical dark energy, $w\ne -1$ and CPL parametrization, as well as different realizations of the sign-switching cosmological constant model.